Control system for a cigarette making machine or the like

ABSTRACT

A control system for a cigarette making machine or the like having a device for feeding shredded tobacco in excess of that required on to a relatively narrow belt to form a filler stream thereon. The belt conveys the filler stream to and through a compression chamber having a valve controlled compressed-air inlet and an air exhaust port, the air compressing the stream within the chamber. A pair of rotary trimming knives removes the excess tobacco from the stream in the chamber and the rod stream formed thereby is advanced to rod former and to other apparatus adapted to form finished cigarettes. A detector is placed adjacent to the rod and provides a signal which is used to control the valve in the compressed-air inlet thereby controlling the degree of pressure in the chamber so that the rod stream produced thereby has a uniform density.

United States Patent [191 Varner [451 Oct. 15, 1974 CONTROL SYSTEM FOR ACIGARETTE MAKING MACHINE OR THE LIKE Donald E. Varner, Columbus, OhioIndustrial Nucleonics Corporation, Columbus, Ohio Filed: Jan. 27, 1961Appl. No.: 85,426

Inventor:

Assignee:

References Cited UNITED STATES PATENTS 9/1946 Richardson 131/84 B UX11/1953 Rault 131/84 12/1953 Milmore 73/194 M X 5/1960 Lanore 131/21 B4/1962 Lanore 131/84 B FOREIGN PATENTS OR APPLICATIONS 12/1951 GreatBritain 131/84 Primary Examiner-Joseph S. Reich Attorney, Agent, orFirm-Anthony D. Gennamo; Robert K. Schumacher; C. Henry Peterson [57]ABSTRACT A control system for a cigarette making machine or the likehaving a device for feeding shredded tobacco in excess of that requiredon to a relatively narrow belt to form a filler stream thereon. The beltconveys the filler stream to and through a compression chamber having avalve controlled compressed-air inlet and an air exhaust port, the aircompressing the stream within the chamber. A pair of rotary trimmingknives removes the excess tobacco from the stream in the chamber and therod stream formed thereby is advanced to rod former and to otherapparatus adapted to form finished cigarettes. A detector is placedadjacent to the rod and provides a signal which is used to control thevalve in the compressed-air inlet thereby controlling the degree ofpressure in the chamber so that the rod stream produced thereby has auniform density.

2 Claims, 7 Drawing Figures Actuator Controller Pmrmw 5w 3.841337 SHEEI281 2 ControHer Actuator Iuvzuron CONTROL SYSTEM FOR A CIGARETTE MAKINGMACHINE OR THE LIKE This invention relates generally to industrialprocess control systems, and more particularly to arrangements forcontrolling the basis weight of a finished product by automaticallyadjusting the density of the material utilized in the process to makethe product.

Various arrangements have been employed in the past for controlling thequantity of material which is continuously introduced into a processdevice in order that the finished product produced by the process devicemay have a uniform weight per unit length. Many of these arrangementshave provided for adjusting the cross-sectional size or shape of themoving strand of material at a trimming station where a portion of thestrand of material may be trimmed off and discarded or recirculated inthe process thereby providing control of the ultimate basis weight ofthe finished product. While these prior arrangements have provedsatisfactory in particular applications, certain disadvantages exist dueto the difficulty involved in mechanically altering the cross-sectionalsize of the moving material flow. This change in size of the materialflow presented to the process device must obviously be compensated forin the process in order that the finished product may be uniform and notreflect the change in size or crosssectional shape of the stream ofmaterial flowing into the process.

The present invention is applicable to a wide class of continuousindustrial processes in which a flow of material is involved that iscapable of having its density altered. More specifically, the control ofthe weight per unit length of a finished product manufactured from suchmaterial is accomplished by feeding to the process a substantiallyconstant cross-sectional area of the material. With this arrangement theweight of material in the finished product is determined by themultiplication of the rate of flow times the cross-sectional area of thematerial times the density of the material. Therefore, by maintainingthe linear rate of flow and the cross-sectional area of the flowconstant, the weight can be controlled directly by controlling thedensity of the material.

It is the primary object of the present invention to providearrangements for the automatic control of industrial processes whichutilize materials which are capable of having their densitiescontrolled.

A further object is to provide arrangements for compressing a stream ofmoving material thereby adjusting the density of material supplied to aprocess for the purpose of controlling the finished product produced.

A still further object of the invention is to provide a combination ofdensity and cross-sectional area control for the material in a processin order to control the final weight of the product produced.

These and other objects of the invention will become apparent from thefollowing detailed description taken in conjunction with theaccompanying drawings wherein:

FIG. I is a schematic elevational view of a continuous process withmechanical means for altering the density of the material supplied tothe process;

FIG. 2 is a plan view of the apparatus of FIG. I with the actuator andcontroller omitted for clarity;

FIG. 3 is an elevational view of a process showing the density controlof a material by means of air pressure;

FIG. 4 is a sectional view taken along the line 4-4 of FIG. 3;

FIG. 5 is a sectional view taken along the line 5-S of FIG. 3;

FIG. 6 is a schematic elevational view of a portion of a cigarettemaking machine adapted to be controlled in accordance with theinvention; and

FIG. 7 is a sectional view taken along the line 7-7 of FIG. 6.

Referring now to FIG. 1, the supply of material 11 to an industrialprocess is obtained by means of a conveyor belt 12 which transports thematerial 11 through a channel 13. This channel confines the horizontaltransverse dimension of the material flow 11. At the delivery end of thechannel 13 a pair of horizontal rotary knife blades l4, 15 are providedto trim the material flow 11 into two portions. A constantcross-sectional dimension portion 16 is defined by the horizontaltransverse interior dimensions of the channel 13 and the distancebetween the bottom of the channel 13 and the horizontal cutting plane ofthe cutting knives l4, 15. The remainder of the material 11 constitutesa discard portion 17 which may be recycled in the process, if desired.The constant crosssection portion 16 is delivered to an input chute 18of a process apparatus 19 in which the material is formed into afinished product 21. The product 21 may be any of the variousmanufactured materials which are formed from raw materials capable ofbeing compressed or expanded to alter the density thereof. The presentinvention is especially suited to a cigarette making process.

The density of the material 11 is altered by controlling the position ofa roller 22 to adjustably compress the material 11 in the channel 13just ahead of the trimming station formed by knives l4, 15. The basicfeed rate for the material 11 is sufficient to maintain the quantity inchannel 13 in excess of that needed for the process. In this way thevertical height of the material flow is higher than the cutting level ofthe knives l4, l5 and the vertical position of the roller 22 willdetermine the density of the material flow as it reaches the trimmingstation.

In order to adjustably position the roller 22, a suitable support, suchas yoke 23, is provided to rotatably support the roller 22 and connectthe same by means of bell crank 24'to an actuating arm 25. The bellcrank 24 is pivoted on a horizontal pin 26 so that the horizontalposition of the actuator arm 25 determines the verti cal position of theroller 22. Various other mechanical arrangements for movably supportinga roller over a compressible stream of material are possible such as,for example, those shown in US. Pat. Nos. 548,686 and 554,635.

The position of the actuator arm 25 may be con trolled by any suitablecontrol system, the one shown in FIG. I being operated by a well-knownbeta ray gauging and control system. In such systems as disclosed andclaimed in US. Pat. No. 2,955,206 to Spergel et al., the mass per unitlength of the material 21 is determined by directing beta rays from asource 27 through the material 21. The unabsorbed radiation detected bya suitable radiation detector 28 is applied to a controller 29 fordeveloping a product variable signal. This variable signal is thencompared with a standard value to produce a control signal in accordancewith the mass per unit length of the material 21. Thus the controller 29provides an operating signal for an actuator 31 of any suitable typecapable of moving the arm 25 in accordance with the signal detected bythe detector 28.

In operation of the system of FIG. 1 the signal detected by the detector28 produces a control signal in controller 29 to energize the actuator31 and adjust the position of the arm 25 in accordance with thedeviation of the weight of the product 2] from the specification weight.This adjustment of the arm 25 has a sense such that if the weight ofproduct 21 is less than the specification value, the arm 25 will move inthe direction to depress the roller 22, thereby compressing the material11 into a more dense condition. In that instance the material in portion16 will have a constant crosssectional size of greater density and hencegreater weight to supply to the process 19. The adjustment to arm 25 ismade in an amount sufficient to make up the deficiency in weight of theproduct 21. If the product 21 is heavier than the specification value,the opposite control signal will raise the roller 22, thereby permittingthe material 1 1 to be less dense. In this instance the mass of theportion of the material 16 entering the process will thus have a lowerweight per unit length of the flow.

Referring now to FIG. 3, a modification of the invention is shown inwhich the density of the material supplied to the process is controlledby air pressure. The material 11 is delivered on belt 12 to a housing 32wherein there is located a forming station 33. The station 33 consistsof suitably shaped die members which progressively form the belt 12 intoa substantially cylindrical shape, with the material 11 containedtherein, as indicated by the cross-sectional view shown in FIG. 4. Afterthe belt 12 is formed into a cylindrical shape, the die extension 34passes through an airtight partition 35 separating the housing 32 from apressurized housing 36. Within the housing 36 the belt guide goesthrough a gradual transition by the forming member. This formingtransition occurs at 37 until at section -5, the belt 12 is laid openand the contents 11 are exposed above the surface of the belt, as shownin FIG. 5. To the right of section 5-5 in FIG. 3, the belt 12 passesover a chamber 38 having an open top in airtight contact with theundersurface of the belt 12. In this modification, the belt 12 will beconstructed of air-pervious material such that air can flow through thematerial 11 through the belt 12 and into the chamber 38. Port 39provides an exhaust for chamber 38 to the atmosphere. Locatedapproximately midway of the longitudinal dimension of the chamber 38 arecutting knives 14, separating the moving strand of material 11 into aconstant crosssectional portion 16 and a discard portion 17. The cuttingplane of the knives 14, 15 is indicated by the line 40 in FIG. 5.

The housing 36 is substantially airtight except for the leakage paththrough the material 11 within the forming members 37 and 34, the exitchute 18, and the exhaust port 39. The length of the path transverselythrough the material within the forming members 37 and 34 and the exitchute 18 is sufficient to maintain considerable air pressure within thehousing 36. High pressure air is supplied to a valve 41 which iscontrollable to vary the pressure within the housing 36 by controllingthe amount of air supplied through conduit 42 leading from the valve 41into the housing 36. The pressure within the housing 36 is effective tocompress the material 11 as soon as the material is positioned above thechamber 38. The amount of compression, and hence the density, of thematerial 11 when it reaches the knife station for trimming by the knivesl4, 15 will be determined by the setting of the valve 41. In accordancewith the invention, the valve 41 is controlled by a suitable detector ofthe weight of the finished product via a control loop similar to thatshown in FIG. 1, with the controller 29 and the actuator 31 operating toadjust the setting of the valve 41.

Referring now to FIG. 6, the modification of a known cigarette-makingmachine to incorporate the invention will be described. The generalarrangement of said machine provides a tobacco feed belt 43 with thestream of tobacco 44 under a pickup wheel 45. The bottom of theperipheral groove 46 is perforated and communicates with the interior ofthe wheel 45. A slight vacuum is drawn by connecting a suitable pump toa pipe 47 communicating with the interior of the wheel 45. The vacuum iseffective to pick up the tobacco 44 in the groove 46 and carry it upwardon the wheel 45 to a position adjacent a cutting wheel 48. The tobaccostream is divided by the cutting wheel into a uniform crosssectionportion 49 and a return excess portion 51. The uniform cross-sectionstream 49 is fed to a rod former 52 encasing the tobacco in cigarettepaper to form a cigarette rod 53. The position of the knife 48 ismanually adjustable to control the cross-sectional size of the stream49.

In accordance with the present invention, the abovedescribed cigarettemaking machine is modified as shown in FIGS. 6 and 7. This adjustment ofboth the density of the tobacco in the stream 49 and the crosssectionalsize of the stream 49 is accomplished without modifying the position ofthe knife 48. Thus, in the present invention the knife 48 occupies afixed position spaced from the periphery of the wheel 45. As shown inFIG. 7, the wheel 45 and the return wheel rotate about a stationary hub54. This hub 54 supports the rotating parts and provides a communicatingpassageway I from the pipe 47 to the interior of the wheel 45. Thecommunicating passageways between the interior of the wheel 45 and thebottom of the peripheral groove 46 are indicated at 55. The hub 54 has asector-shaped extension 56 to render the vacuum within the wheel 45inefi'ective over that portion of the peripheral groove 46 adjacent thearcuate boundary of the sector 56. Thus the tobacco 44 is not influencedby the vacuum when it arrives at the cutting station of knife 48.

The density of the tobacco 44 at the knife 48 and the cross-sectionalsize of the stream 49 are determined by the horizontal position of awheel 57. There is provided on wheel 57 a continuous flange rim 58 withthe end face thereof forming one side wall of the peripheral groove 46.The flange wheel 57 is mounted for rotation with the wheel 45 by aplurality of pins 59 projecting from the surface of the wheel 45. Thesepins 59 make a sliding fit with holes 61 in the wheel 57. The wheel 57is connected by a shaft 62 to an actuator capable of moving the assemblytoward or away from the wheel 45, as indicated by the double-headedarrow in FIG. 7.

The control system shown in FIG. 6 is substantially identical with thatdescribed for FIG. 1 with the actuator 31 operating to control thehorizontal position of the shaft 62. The quantity of tobacco in thegroove 46 is thereby viewed to provide control of the weight of thetobacco in the stream 49. The tobacco stream is then utilized to formthe cigarette rod 53. Variations in the position of the shaft 62 causegreater or lesser amounts of tobacco to be trimmed off and recirculatedin the stream 51. As hereuntofore described the system provides aneffective control means for selecting that portion of the tobacco stream44 which is utilized in making the cigarette rod 53.

Many modifications of the invention will now be apparent to thoseskilled in the art, and such modifications together with the variousequivalents of the disclosed embodiments are to be considered within thescope of the invention as defined in the appended claims. Thisapplication is directed to improvements on the invention disclosed inthe co-pending application of Victor S. Levadi, Ser. No 85,228 nowabandoned.

I What is claimed is: I

1. In an industrial processing system using compressible material toform a product and including a conveyor for said material, and means forfeeding an amount of said material to said conveyor in excess of thatrequired to form the product, the material on said conveyor having afree surface, a control system for controlling the quantity of saidmaterial used in forming said product, said control system comprisingseparating means for separating said material into a first portion ofpredetermined cross section and a second portion containing the excess,adjustable means comprising an air jet of adjustable magnitude forpressing the free surface of said material with a pressure exceedingatmospheric pressure toward said conveyor ahead of said separating meansthereby controlling the density of said material as conveyed to saidseparating means, means for feeding said separated first portion to formsaid product, detecting means for detecting the quantity of saidmaterial in said product, and means responsive to said detecting meansfor controlling said adjustable means in accordance with the quantity ofsaid material detected to maintain said quantity constant.

2. In an industrial processing system using compressible material toform a product and including a conveyor for said material, a station forthe material on said conveyor, and means for feeding an amount of saidmaterial to said conveyor in excess of that required for said product, acontrol system for controlling the rate at which said material is usedin forming said product, said control system comprising adjustable airpressure means for varying the density of the material conveyed to saidstation, said adjustable air pressure means having a substantiallyair-tight housing adapted to contain said station and have said materialenter said housing on said conveyor and exit to said process, a chamberwithin said housing and separated from said material by an air permeablewall, means for applying adjustable air pressure in said housing, andmeans for venting said chamber to a pressure lower than that in saidhousing; means at said station for separating said material into a firstportion of predetermined cross-section and a second excess portion;means for feeding said separated first portion to form said product;means for detecting the quantity of said material in said first portion;and means for controlling said adjustable air pressure means inaccordance with the quantity of said material detected to maintain saidquantity constant.

1. In an industrial processing system using compressible material toform a product and including a conveyor for said material, and means forfeeding an amount of said material to said conveyor in excess of thatrequired to form the product, the material on said conveyor having afree surface, a control system for controlling the quantity of saidmaterial used in forming said product, said control system comprisingseparating means for separating said material into a first portion ofpredetermined cross section and a second portion containing the excess,adjustable means comprising an air jet of adjustable magnitude forpressing the free surface of said material with a pressure exceedingatmospheric pressure toward said conveyor ahead of said separating meansthereby controlling the density of said material as conveyed to saidseparating means, means for feeding said separated first portion to formsaid product, detecting means for detecting the quantity of saidmaterial in said product, and means responsive to said detecting meansfor controlling said adjustable means in accordance with the quantity ofsaid material detected to maintain said quantity constant.
 2. In anindustrial processing system using compressible material to form aproduct and including a conveyor for said material, a station for thematerial on said conveyor, and means for feeding an amount of saidmaterial to said conveyor in excess of that required for said product, acontrol system for controlling the rate at which said material is usedin forming said product, said control system comprising adjustable airpressure means for varying the density of the material conveyed to saidstation, said adjustable air pressure means having a substantiallyair-tight housing adapted to contain said station and have said materialenter said housing on said conveyor and exit to said process, a chamberwithin said housing and separated from said material by an air permeablewall, means for applying adjustable air pressure in said housing, andmeans for venting said chamber to a pressure lower than that in saidhousing; means at said station for separating said material into a firstportion of predetermined cross-section and a second excess portion;means for feeding said separated first portion to form said product;means for detecting the quantity of said material in said first portion;and means for controlling said adjustable air pressure means inaccordance with the quantity of said material detected to maintain saidquantity constant.